Numerical analysis using three-dimensional CAD data uses a method for modeling analysis object CAD data with mesh data comprising a polygon element and a polyhedron element. In particular, when an analysis object is a thin-plate structure, data is converted into a shell mesh comprising triangular elements and quadrilateral elements, and thereby a calculation cost on analysis is restrained. In relation to this technique, a technique is known that extracts each nodal point constituting part of tetrahedron mesh data, integrates nodal points at both ends of an element side into one nodal point at the center, and thereby generates mesh data (for example, see Patent Literature 1).
Mesh data desired by a device user is usually changed by an objective of analysis, however, and a method described in Patent Literature 1 requires modification of mesh data, and therefore has a problem of increased work-hour. As a solution to the problem, a technique is known that supports generation of analysis mesh data by using existing mesh data (for example, see Patent Literature 2). In particular, the technique compares analysis object CAD data with a shape of existing CAD data stored in a database, performs shape division into a similar shape portion and a non-similar shape portion, and generates analysis mesh data by combining mesh data generated for the non-similar shape portion, and existing mesh data applied to the similar shape portion.